1. Field of the Invention
The present invention relates to a tilting mechanism applicable, for example, to a reclining vehicle seat and a tiltable vehicle steering shaft. More specifically, the present invention pertains to a tilting mechanism having a tilt angle memorizing device.
2. Description of Prior Art
Conventionally, in a vehicle reclining seat, there is provided a movable bracket secured to a seat back and mounted for pivotable movement about a shaft on a stationary bracket secured to a seat bottom frame. Usually, the movable bracket is provided with a sector member having gear teeth formed along its arcuate periphery. A pawl member is swingably mounted on the stationary bracket and has pawls or gear teeth which are adapted to be brought into engagement with the gear teeth on the sector member. An actuating lever is provided for rotational movement about the shaft on which the movable bracket is mounted. The actuating lever is interconnected with the pawl member through a cam mechanism so that a rotational movement of the lever causes a swinging movement of the pawl member to move the pawls thereon into or out of engagement with the gear teeth on the sector gear member. The actuating lever is spring biased so that it normally forces the pawl member into a position wherein the pawl teeth are engaged with the gear teeth on the sector. An actuation of the lever against the spring biasing force causes a swinging movement of the pawl member so that the pawl teeth are disengaged from the gear teeth on the sector to release the movable bracket and the seat back for tilting movement about the shaft. The movable bracket is provided with a return spring which functions to normally maintain the seat back in an upright position. The seat back can be moved into a tilted position against the action of the return spring while the actuating lever is in the actuated position. When the actuating lever is released with the seat back tilted into a desired position, the pawl member is forced by the actuating lever into the position where the pawl teeth are engaged with the gear teeth on the sector.
The conventional reclining vehicle set is also structured so that the seat back can be folded forward. This structure is convenient particularly for use in two-door cars having front and rear seats because an adequate opening can be provided by folding the seat back forward to allow a passenger to get in and out of the rear seat. It has been found that this type of reclining seat is inconvenient in that, once the seat back is folded forward from a tilted position and it is returned to the upright position it is not returned to the original tilted position so that a tilting adjustment becomes necessary after the seat back is returned to the upright position.
In order to solve the problem, Japanese utility model publication No. 55-47406 proposes a seat back tilting mechanism having a tilt angle memory device. In the proposed structure, the actuating lever for the seat back tilting mechanism is provided with a push button which is connected with the tilt angle memory device so that the memory device is actuated to memorize the seat back tilt angle when the push button is depressed. It should however be noted that the proposed structure is inconvenient for use because the push button must be depressed independently from the actuation of the lever in order to have the tilt angle memorized.